Air-brake lock



Feb. 16,1926. B. W. WESTBO ET AL AIR BRAKE LOCK Feb. 16 1926. 1,573,597

B. W. WESTBO ET Al.

AIR BRAKE Loox Filed sept. 10, 1924 2 sheets-Sheet 2 f such reduction iscaused 'by @J1 QPQDU kreunited Feb. 16, 1926.

UNITED STATES PATENT oFFlcE. 'y

BERNHARD WESTBO AND vIPERCIVAL N.V BISSON, OlE SOUTH PRAIRIE, WASHING-TON, ASSIGNORS TO RAILWAY SAFETY BRAKE LOCK CORPORATION, TACOMA,

WASHINGTON.

A AIR-BRAKE Loox. 5

, Application fiiedseptembr ib, i924, 'serial no. 736,854.

To @ZZ 107mm it may conce/m:

Be it known that we, BERNHARD no and Pnnoivixi. N. Bisson, citizens ofthev United States, and residents of. South Prairie, Pierce County,Washington, have invented certain new and useful Iniprovements inAir-BrakeV Locks, of which the following is a specification'. l l f Thisinvention' relates to improvements in air brakes andv particularly toair brake locks of that character for preventing the releaseof a brakeincidental to a reduction of air pressure in the brake cylinder thatmight occur because of leakage, exhaustion of supply or accident to pipeconnections.

To better explain the purpose of the invention, we will state that the.present loclc ing mechanism is intended for use inconnection with theair brake as now used. lon railway ,rolling stock'and which is acoinbination of parts controlled 'and operated by y compressedl air.More specifically stated, such mechanism consists of asource of vcoin-`pressed air supply, a brake valve by means ofwhich an engineer canapplyor release the brakes, a brake pipe,` or trainy line, by means of whichconnection is made between the brake valve and brake apparatus of eachcar in a train, a brake cylinder by nieansof which the power storedin'jcoinpresised air maybe transformed into mechanical force to a brakegearconsistingV of various frods, brake shoes and other requiredconnections whereby theA brake shoes may be applied to the wheels of acar to. retard it.

In connection with the abovey parts there is also included for eachseparate vehicle,'an auxiliary reservoir in which a 'supply yofcompressed air is stored suliic-ient to operf ate the brake on thatvehicle, a tripple valve to which the brakepipe, lauxiliary reservoirand brake cylinder are connected and which serves to control the flow ofair from' the brake pipefto the auxiliary reservoii when 4c liaiging,from the `auxiliary"reservoir vto tlieb'rake cylinder when applying andfrom the brake cylinder to atmosphere `'when releasing the brake; Thenthefb'rakes are notV being used, the brake pipe and auxiliary res-fervoii' are chargedand' maintained l,at a iXed normalv pressure.,'.The-brakes are ap-- plied by reducing the pressurefiln the brake pipebelow that in the auxiliaryreservor.

can again be built up.

j Y beinginade from the brake pipe', or its con- W lVEs'i-,

nections, to atmosphere and may be intentional as when the engineeropens the brake valve orac'cidentally as in case of the braking of apipe or hose.4 To those familar with train operation, it is known thatif a trainv of cars equipped with airubrakes'i's* disconnected from theVengine which furnishes the' source of air-l` supply, the brakesof allcars will be applied for the reason that opening the train line destroysthe equality of brake line and auX- iliaiy reservoir pressure causing,the tripple Valve of .each rcar to operate to apply `the brakes byadmitting compressed air'froni `the auxiliary reservoir to the brakecylinder.

Itis further vknown that -for various reasons, after a'brake has',lbeenset, the vvair will gradually leak from'tlie brakecylinder andpermitthefbrake to be released." Then vif. the train happens to bestanding'on a grade it may start` to roll unless thev hand brakes, ywithwhich cars are usually equippedl have beenlfset.y

It isv furtherjknown that the air supply I of vtrains sometimes is usedfaster than it can be supplied. 1 This is most apt to occur with heavytrains'operating on long e down grades, and when such does occur thehand brakes must be resorted to and dependeduponentirely until thesupply of air y `rInpfview of these undesirable result-s due tofairleakage or exhaustion of` supply, it lhas beenthe object `of thisinvention to provide automatically operating locking meansy for use 1nconnection with `brakes of the above character that will moveintoxposition for holding abrakewhen set vshould the pressure of air inthe brake :eylindersfor any reason fall below a-certain pre-determinedamount and which will move to non-functional position when a safeworking-piessure has again been reservoir. i

Another object stated'that.1nay*be manuallyset or released and whichmayj be installed on the regular ybrake equipment of railway cars builtup inV theL auxiliary Y of the invention vresides .in the provision oflocking devices, as above .Cil

the various details of construction and combination out parts of theautomatic locking device and in their mode of operation.

ln accomplishingthese and other objects ot the invention, We haveprovided the improved details of construction, the preferred forms ofwhich are illustrated in the accompanying' drawings, wherein Figure l isa ragmental side elevation ot a car having an air brak mechanismequipped Withan automatic lockinginechanismv in accordance With thepresent invention. v Figure mechanism.

Figure 3 is an enlarged, side view of the locking mechanism.

Figure el is enlarged sectional View ot the air controllea'l valvemechanism for controlling` movement oi the locking;` dog; With respectto the locking,1 ratchet.

Figure 5 is an end view of' the brake mechanism showing the connectionsfor manual release of the lock.

Referring` more in detail to ingsl designates what may be a railway car,equipped with air brake mechanism of that type in connection `with Whichthe present automatic locking' device is used. The air brake mechanismis of the usual. Jform now generally used on all railway cars andconsists principally of the train pipe 2, through Which compressed airis delivered vtrom a source of supply, not shown, along; the train tothe individual brake n'iechanism of each car, an auxiliary reservoir 3,that is connected so as to ybe charged from the train line through apipe Lland an interposed tripple valve mechanism, designated at 5 and acar brake cylinder 6 that receives its air from the auxiliary reservoir,under control ot the tripple valve.

VYithin the brake cylinder S is a piston 7 adapted to be moved outwardlyagainst the resistance ot a coiled spring' 7 by the admittance of air tothe cylinder and tixed to the piston is a rod 8 which, at its outer ond,connects pivotally as at 9, with a lever l() to which in turn areconnected rods or cables ll and l2 extended to the brake beams orcorresponding; parts, not shown, at opposite ends oi a car and 1whichcarry brake shoes that are adapted to be pressed into engagement withthe car Wheels when it is desired to retard or stop the car. The pistonrod 8 connects with the lever l() at a point approximately two-thirds otthe distance between its ends and the rods ll and 12- are pivotallyattached to the lever, respectively, at the Aextreme end ot the longersection and intermediate this end and the pivot connection ivith pistonrod, the parts oper so that when air is admitted vfrom the ausiiiaty.reservoir tof-cylinder G, which' a plan vie-w ot the braking thedrawpiston 7 and rod S outwardly, the lever l() is so moved as to causebrakingtension on both rods ll and l2.

The lociing' mechanism embodied by the present invention is mounted uponabase plate 2O which is vertically disposed against the side of brakecylinder 6 and is lined theretoby means of bolts *2l extended through alaterally turned flange 22 along the top edge ot the plat-e and a.supporting` flange 23 formed integral With the cylinder 6. rlhese boltsmay also serve to support the brale cylinder from the car structure.

Cast integral with the plate 2O at its opposite side edges are guides 2dand 25 through which a lock bar 26 is slidably extended. Along its upperedge the bar is provided with ratchet teeth 27 and near one end it has aloop 27 into 1which one end of the brake lever'l() extends and whereinit is fixed by a pivot'pin 28. The connection and mountingof the partsis so arranged that the lock bar slides back and forth in itsmountingsin accordance with the movement of the lever l0 influenced by the handor air brake. i

To the outer end of the lock bar QG a cable 13 is attached which extendsto the hand brake shaft 16 at the end ot the car. -This cable may beWound on the shaft by rotation of the brake Wheel i7 at its upper end itit is desired to set the brake by hand,

Pivotally tixed to the base plate 2O by means of a bolt l() is a lockingdogg 3l having a pivotally mounted paivl at its end adapted to holdinelyengagel With the teeth 27 of the locking' bar. Normally, that is whenthere is sutiicient air pressure in the auxiliary reservoir 3 to holdthe brakes set, the locking' means is not needed andthe pavvl nelddisengaged from the teeth of the locking bar by means presentlydescribed, but soon as 'this pressure approaches the point at which itwill become insufficient to hol( the brake, the par-:l permitted to moveinto holding` engagement with the teeth ot the loclr bar so that thelatter cannot move inwardly and the brake beam Will be held thereby sothat the brakes cannot be released.

T he means iustreterred to tor controlling; movement ot the locl in'doe'` as beat shown in Figures B and ll, consistent aplunger connectedat its lower end with a piston 3 operable in an air cylinder under thecontrol of air from the auxiliary rc ervoir. At the upper endV ot theplunger A, a head 38 adapted, when the plunger is extended', to engagewith a roller 23S), Vsupported by a pin el@ from the dog` to therebvlitttlie nog and'loclring "li'iom the ra eetlr ll'heh the pinne iretacts, the dog is t ee to more toi finit the pavfl to, locl with thereel; haii. 'Y

An important feature the in-i-entien pipe 46 is connected.

resides inthe construction :and manner el 'pin 10 that mo-unts ltheroller Its upv-` ward pivotal movement is limited by contact with anadjusting screw l-l thatlis'tlneaded through an extension@ from the endof the dog overlying the pawl. A'cciled spring 423 located about the pinl0 bears against. the pawl to retain it yieldingly in place Ybutwhen'pressureis exerted by the plunger up.- wardlyagainst the roller thelocking device will Yhinge upwardly atthe pivot point l0 and thus thelocl bar willbe released. Y As soonl as the pawl is disengaged `from therack,

the spring 43 brings it back to normal position. lllithout this featureet' construction,- an excessive amount of pressure would be required torelease the pawl it' there is any-YA tension on the V.brake beam. n

The air'cylinder'( is VVmounted on a valve housing 45 supported from theplate 20 and connected with one end of this housing is :i pipe 46leading` from the ltrain pipe 2. A; pipe L7- connects with the lower:end ofcylinv der 37 and with the Valve housing and interposed in thehousing between the connec-` tions therewith of pipes 46 and l'is a vayc 4S that controls the flowy of airftrom the train pipe to thecylinden?. l/Vhen the pressure cgtV a-ir inv cylinder 37"*'alls belowacertainV pre-determined amount, the pist-on 36 will be moved to its'lower limitof-travel and the plungerjV retracted byfmeans of al coiledspring 49 enclosed within thecylinder and bearing downwardly against thepiston,- but when. the'train line is lcharged to a certaindesirable'operatingpressure and this pressure is admitted throughpipesd, and 4-.7 to the cylinder 37, the plunger willbe extended..y Y YAn air exhaust pipe 5() connects with the lower end of the cylinder 37and to the end of the Valve housingd lopposite that to which This pipecommunicates with ai chamber 5l in the housing provided with exhaustports 52. A valve 53 invterposed in thehousing between chamber 51 andpipe connection controls the flow or" air froml thel cylinder.

The Valve 48 is of conical forin and adapted toa seat 5ft inthe housingagainst which it is yieldingly held by a coiled spring 55 that bearsagainst its 'outer side and against. a seat :36in a nipple`'threaded'into the housing. y-A'variation inthe holding tension of thespring-is obtained by vadiestynient of the nipple.. Theralve also yhaskanv inwardly extending stemrS by means of which it is moved to openposition, as will presently beV described-- The valve 58 likewise is ofconical form and is adapted toa seatO. A spri'ng VGlcontained within" anippleV 62 bears againstl a shoulder l63 on the stem 64 .of the 'latterValve to yieldinglyv retain it open and the tensionof this spring may bevaried by adviustmentot' the nipple.

i Centrally of the housing e5 is a chamber 10, closed at its oppositesides by- Aflexible diaphragme 7l and 72 and a conduit 'i' connects thischamber lwith t-he auxiliaryfreservoir 3. By this connection an equalityot .pressure .is maintained in thereservoir and chamber. Slidablymounted in the housing and vheld against the outer face ot diaphragm 7lbypmeans of a spring 74, is 'a hollow plunger and a coiled spring 76contained within the plunger bears against the inner end of a slidablymounted pink". which at `its outer end, engages the stem of valve 48.Likewise' a` plunger V80 is located in the other end vot the valvehousing" which is held with its inner end against the outer face ofdiaphragm 72 by a coiled- ,pring 81 and atits outer-end ithas a stemv S2adapted to engage with the Valve 53lv Thetwo plungers and 8O moveoutwardly and inwardly in accordance *withA contraction or expansion ofthe diaphragms with which they connect and the diaphragme move'outwardly orinwardly in accordance withl the pressure of air in chamberVFO wliich,gby virtue of pipe connection 73, is maintained the same asthat -in the auxiliary reervoir. f

' vV/Tith the parts ate as follows: lVhenthe auxiliary reservoir vischarged 'to' a suitable working pressure,- vthis pressure willy becommunicated to so constructed,- it will oper-VA f i chambersTOf'through pipe 7 3 and the diaphragms 71l and 72 will be' expanded sothat by the means previously described, the valve L1:8 will be openedand valve 53 will be closed; The opening of valve 48 permits a vflow ofcompressed air from the train line to pass .into cylinder 37 to extendthe plunger 35 so that the locking dog is held disengaged from the lockbar. Thus, so long as thereis a certain desired working pres-` sure ofair in theauxiliary reservoir, the

brake operates the same'y as if the present attachment was -notused. v l

Assuming thenthat the brake of a carrhasl j v been set byair and thatfor some reason such lasa leakage or exhaustion of supply, the

pressure of air in the' auxiliary reservoir appreaches apoint at whichit. would be insufficient to hold the brakes set. When this v conditionis reached, the Valve 48 in housingr The. closing; ofwrvalve' 48 cutsottany supply .i

4t-5 closes and valve opens for thereasen that air pressure 1n chamber70 decreases V1n accordance withthat in the reserroir.3` y

" tends upwardly through suitable guides et air trom the train line andthe opening o'l valve 53 permits air to escape troni cylinder 23T sothat the plunger Will retract and the locking dog will drop into lockingengagement with the lock bar and hold it against release movement.

lllhen the auxiliary reservoir is recharged to a desirable pressure, thediaphragms will be expanded so that valve 'will be opened and ralveclosed. Air will then flow iroin the train line into cylinder 37 andmove the piston and plunger so as to again release the dog,

For the purpose olf manually releasing the dog' from the lock bar by aperson on top of the car, We have provided bell crank lever that ispivotally fixed by a bolt 91 to plate 2i). rlhis crank has an arm eX-tended beneath the roller on the dog 31 and another arm $3 extendingupwardly to which chain 94- attached. rl`liis chain connects with onearm ot a bell crank 95 pivotally mounted at the end oit the car. A rod96 fixed to this latter cranl and e5;-

to a point adjarentthe hand brake wheel. By pressing' downwardly on thisrod the crank arm 92 `Will be thrown upwardly against roller 39 todisengage the pawl 82 from the teeth et the rack or lock bar. A soring97 connected With rod 96 returns it to normal position.

To pernnt the manual release of 'the loclr by a person at either side ofthe car, We have provided a release lever 100 that is pirotallysupported centrally by means ot a bracket 101 from plate 2G. Rods 10Qand loi-.l are attached to its opposite ends and these are extended toopposite sides of the car. in arm 10a'- extends from the lever 100 andis adapted to be moved into lifting engagement with a downturned endportion 105 or' lever arm 92 ot bell crank 9() by outward pull on eitherrod 102 or 103, to thereby cause arm 92 to lift the locking dog byengagement with roller 39.

VlT/Then the car is entirely nisconnccted from a source ot compressedair, the brakes may be operated by the hand brake in the usual mannerand will be locked when set by the present locking devic Having thusdescribed our invention, what ive claim as new therein and desire tosecure by Letters-Patent is:

l. rlfhe combination with an air brake mechanism ot the characterdescribed in- ',rluding a train pipe, an auxiliary supply rcservoir anda brake lever, oi a normally disengaged locking means for the bralrelever adapted to be set under the control ol' air pressure in the trainpipe and to be released under control ot air pressure in the auxiliaryreservoir.

2. The combination with an air brake mechanism of' the dass detained.inf/illldlls a train pipe, an auxiliary reservoir and .a brake lever, otlocking mechanism tor the brake lever whereby the brakes may be retainedset, means operable by the pressure 0l' air in the train line forretaining the locking mechanism in non-functional position and othermeans operable under the control of air in the auxiliary reservoir torcontrolling the operation ot the lirst mentioned means.

ln a device ol' the class described, theekv combination with an airbrake y'system including a train pipe, an auxiliary reservoir, a brakecylinder, a piston in said cylinder and a brake lever connected Withsaid piston, ot a lock bar .attached to said lever, a paWl adapted tolock With the bar to retain the brakes set and means operable under thecontrol of pressure Within the auxiliary reservoir fornormally'retaining the pawl disengaged Yfrom the lock bar but Whichpermits it to move into locking engagement with the bar When pressureWithin the reservoir falls below a predetermined amount.

il. ln a device of the class described, the combination with an airbrake system including a train pipe, an auxiliary reservoir, a brakecylinder, a piston in the brake cylinder, a piston rod connected 'withthe piston and With a brake actuating lever oi' a toot-hed lock barconnected with the said lever, a pawl adapted tor locking engagementwith said bar, an air cylinder, a piston in said cylinder, a plungerattached to the piston, means connecting the air cylinder with the trainpipe whereby air pressure from the latter will extend the piston and itsplunger against the paivl to retain the latter disengaged from the lockbar and valve mechanism operable under the control ot pressure ot air inthe auxiliary reservoir tor releasing or admitting air into the aircylinder for the purpose of releasing or setting the locking paWl.

5. In a device of the class'described, the combination with an air brakesystem including train pipe, an auxiliary reservoir, a brake cylinder, apiston in the bralre cylinder, a piston rod connected with the pistonand with a bralre actuating lever ot' a toothed lock bar connected withthe said lever, a pawl adapted for locking engagement with said bar, anair cylinder, a piston in said cylinder, a plunger attached to thepiston, a yieldable means for, normally retaining the plunger inretracted position, a conduit connecting the air cylinder and trainpipe, a valve operable to cont-rolV the iloiv ol air through saidconduit and means operable under the control of air pressure in theauxiliary.reservoir tor opening said valt-re to admit air to said aircylinder when pressure in the reservoir exceeds a certain predeterminedamount to thereby more the pieten te extend, the' Pullsel"Y te lil@ thelocking pawl released from the lock bar and operable to closesaid valveand vrrelease air from the air cylinder when the a conduit connecting`said cylinder and train pipe, piston -iii said cylinder operable by theadmittance oi' air from the train pipe to release the pawl. from thelock bjar and a valve mechanism koperable under the control of air underpressure inthe auxiliary reservoir for admitting air into and releasingit 'from the air cylinder. A A j 7. In a device ol the class described,the

Vconibination with an. air 'brake lsystem ino y, cluding a train pipe,an auxiliary reservoir,

a brake cylinder, apiston in. the brake cylinder a brake actuating leverand a )isu 7 V D yten rodconnecting the piston and lever, of

a toothed locl bar attachedv to the brake lever, a pawl adapted toengage with the bar to lool: the brakes, an air cylinder, a

conduit connecting said' cylinder and train pipe, valve mechanism forcontrolling the dow of aiithrcugli' said conduit intoV the air cylinder,another valve mechanism operable.v

to control the exhaustion of air from the cylinder, and a controlmechanism operabley under the influence otair pressure in the auxiliaryreservoirY for controlling said valve Vmechanisms. v

8. in a device of the class described, the combination with anl airbrake system including train pipe, an auxiliary reservoir,` a braliecylinder, a" piston inV the brake cylinder, a brake actuating lever andapiston rod connecting the piston and lever Vorga toothed lock -barattached to the .brake lever, a locking pawl lmovable from and intolocking relation with saidbar, means operable automatically under thecontrol of air pressure within the auxiliary reservoir for" actuatingthe pawl between released and locking relation with the .lock bar andmanually operable means for releasing the pawl from the lock bar.

9. In a device of the class described, the

combination with an air brake system including a train pipe, anauxiliary reservoir',

the pawl to lock vwith the a brake cylinder, a piston 'in the brakecylinder, ay brake actuating lever and a piston rod-connecting thepiston and lever of a toothed lock bar attached tothe brake lever,afpivoted locking pawl movable from and into locking relation with saidbar,fan air cylinden'fa piston in saidcylinder, a plunger attached tothe piston and extendable from the cylinder to release the pawl from4the lock bai', a conduit connecting the air cylinder and train linewhereby air advinitted under pressure from the train line will extendthe plunger to release the pawl, a control valve in said conduit, anexhaust conduit for the aii'cyliiider, a control valve in Saidv exhaustconduit and actuating mechanism for said control valves including' achamber with yieldable diaphragms forining walls thereof and operatively-connected f vvvith the valves and av Vconduit connecting' Vsaid chamberwith the auxiliary reservoir whereby a variation of pressure of air'within thelatter effects contraction or eX- fpansion of saiddiaphragnis to open or close.

said valves.. l o

l0. In a device of the class described, the combination with an airbrake systemincludinor a train pipe, an auxiliaryV reser-v voir, a brakecylinder, a piston inthe brake cylinder, and a brake actuating leverfoicaV toothed lockbar attached to the brake lever,

e' a pivoted locking pawl movable from and'v into locking relation withsaid bar, an air cylinder, a piston in said cylinder, a plunger attachedto the piston and extendable Yfrom the cylinder to release the pawl'froinv'thc lock bar, a conduit connecting the air cylinder and trainline whereby air admitted *f under pressure from the train lineA willextend the plunger to release the pawl, a control valve in said conduit,an exhaust con-4 duit for the air cylinder, afcontrol valve in vsaidexhaust conduit 'and actuating mechaV- .n ism for said control valvesincluding a chamber with yieldable diapliragnis forming walls thereofand operatively connected` with the valvesand a conduit connectingsaidchamber with the auxiliary reservoir whereby a variation or"pressurey of air 'within 'the latter effects contraction or expansion ofsaid diaphragme Vto open or close said valves, and adjustable means forvary- Iing the degreel of expansion of the diaphragme required foractuating the control valve mechanisms.

Signed at Tacoma, Pierce County, Washington, this 14th day of July 199A.

BERNHARD w. wEsTBo.

riiRoivAL N, Bisson. f

